Unity异步编程Task.Yield与Task.Run的使用

Task.Yield有点像携程中的yield return new WaitForEndOfFrame()

在unity中就是下一帧继续(首次await Task.Yield()后还是在当前帧的末尾，此后就是等下一帧)

当然继续还是在主线程中

async void RunTestTask()
{
    Debug.Log("ThreadId begin " + Thread.CurrentThread.ManagedThreadId.ToString());
    var testTask = TestTask();
    while (!testTask.IsCompleted) await Task.Yield();
    Debug.Log($"RunTestTask over rtn {testTask.Result} ManagedThreadId {Thread.CurrentThread.ManagedThreadId.ToString()}");
}
async Task<int> TestTask()
{
    Debug.Log("TestTask begin " + Thread.CurrentThread.ManagedThreadId.ToString());
    await Task.Delay(1000);
    Debug.Log("TestTask end " + Thread.CurrentThread.ManagedThreadId.ToString());
    return 998;
}

ThreadId begin 1

TestTask begin 1

TestTask end 1

RunTestTask over rtn 998 ManagedThreadId 1

 

 

Task.Run会启动一个新线程

async void RunTestTask2()
{
    Debug.Log("ThreadId begin " + Thread.CurrentThread.ManagedThreadId.ToString());
    var testTask = TaskYieldSimulation();
    while (!testTask.IsCompleted) await Task.Yield();
    Debug.Log($"RunTestTask over ");
}
Task TaskYieldSimulation()
{
    Debug.Log("TaskYieldSimulation before await, current thread id: {0}" + Thread.CurrentThread.ManagedThreadId.ToString());
    return Task.Run(() =>
    {
        Debug.Log("TaskYieldSimulation before ContinueWith, current thread id: {0}" + Thread.CurrentThread.ManagedThreadId.ToString());
        Thread.Sleep(3000);//阻塞线程3秒钟，模拟耗时的操作
        Debug.Log("TaskYieldSimulation ContinueWith!");
    }).ContinueWith(t =>
    {
        Debug.Log("TaskYieldSimulation after await, current thread id: {0}" + Thread.CurrentThread.ManagedThreadId.ToString());
        Thread.Sleep(3000);//阻塞线程3秒钟，模拟耗时的操作
        Debug.Log("TaskYieldSimulation finished!");
    });
}

ThreadId begin 1

TaskYieldSimulation before await, current thread id: 1

TaskYieldSimulation before ContinueWith, current thread id: 88

TaskYieldSimulation ContinueWith!

TaskYieldSimulation after await, current thread id: 88

TaskYieldSimulation finished!

RunTestTask over

 

以上两种方式均不会卡Unity主线程